/*
 * Copyright (C) 2014 Saravan Pantham
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.jams.music.player.Utils;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.os.Build.VERSION;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;
import android.util.Log;

/******************************************************
 * Takes in an input bitmap, applies a gaussian blur
 * effect to it, and returns the blurred bitmap.
 ******************************************************/
public class GaussianBlur {

    @SuppressLint("NewApi")
    public static Bitmap fastblur(Context context, Bitmap sentBitmap, int radius) {

    	try {
    		if (VERSION.SDK_INT > 16) {
                Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);

                final RenderScript rs = RenderScript.create(context);
                final Allocation input = Allocation.createFromBitmap(rs, sentBitmap, Allocation.MipmapControl.MIPMAP_NONE,
                                Allocation.USAGE_SCRIPT);
                final Allocation output = Allocation.createTyped(rs, input.getType());
                final ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
                script.setRadius(radius /* e.g. 3.f */);
                script.setInput(input);
                script.forEach(output);
                output.copyTo(bitmap);
                return bitmap;
	        }
	
	        // Stack Blur v1.0 from
	        // http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html
	        //
	        // Java Author: Mario Klingemann <mario at quasimondo.com>
	        // http://incubator.quasimondo.com
	        // created Feburary 29, 2004
	        // Android port : Yahel Bouaziz <yahel at kayenko.com>
	        // http://www.kayenko.com
	        // ported april 5th, 2012
	
	        // This is a compromise between Gaussian Blur and Box blur
	        // It creates much better looking blurs than Box Blur, but is
	        // 7x faster than my Gaussian Blur implementation.
	        //
	        // I called it Stack Blur because this describes best how this
	        // filter works internally: it creates a kind of moving stack
	        // of colors whilst scanning through the image. Thereby it
	        // just has to add one new block of color to the right side
	        // of the stack and remove the leftmost color. The remaining
	        // colors on the topmost layer of the stack are either added on
	        // or reduced by one, depending on if they are on the right or
	        // on the left side of the stack.
	        //
	        // If you are using this algorithm in your code please add
	        // the following line:
	        //
	        // Stack Blur Algorithm by Mario Klingemann <mario@quasimondo.com>
	
	        Bitmap bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
	
	        if (radius < 1) {
	                return (null);
	        }
	
	        int w = bitmap.getWidth();
	        int h = bitmap.getHeight();
	
	        int[] pix = new int[w * h];
	        Log.e("pix", w + " " + h + " " + pix.length);
	        bitmap.getPixels(pix, 0, w, 0, 0, w, h);
	
	        int wm = w - 1;
	        int hm = h - 1;
	        int wh = w * h;
	        int div = radius + radius + 1;
	
	        int r[] = new int[wh];
	        int g[] = new int[wh];
	        int b[] = new int[wh];
	        int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
	        int vmin[] = new int[Math.max(w, h)];
	
	        int divsum = (div + 1) >> 1;
	        divsum *= divsum;
	        int dv[] = new int[256 * divsum];
	        for (i = 0; i < 256 * divsum; i++) {
	                dv[i] = (i / divsum);
	        }
	
	        yw = yi = 0;
	
	        int[][] stack = new int[div][3];
	        int stackpointer;
	        int stackstart;
	        int[] sir;
	        int rbs;
	        int r1 = radius + 1;
	        int routsum, goutsum, boutsum;
	        int rinsum, ginsum, binsum;
	
	        for (y = 0; y < h; y++) {
	                rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
	                for (i = -radius; i <= radius; i++) {
	                        p = pix[yi + Math.min(wm, Math.max(i, 0))];
	                        sir = stack[i + radius];
	                        sir[0] = (p & 0xff0000) >> 16;
	                        sir[1] = (p & 0x00ff00) >> 8;
	                        sir[2] = (p & 0x0000ff);
	                        rbs = r1 - Math.abs(i);
	                        rsum += sir[0] * rbs;
	                        gsum += sir[1] * rbs;
	                        bsum += sir[2] * rbs;
	                        if (i > 0) {
	                                rinsum += sir[0];
	                                ginsum += sir[1];
	                                binsum += sir[2];
	                        } else {
	                                routsum += sir[0];
	                                goutsum += sir[1];
	                                boutsum += sir[2];
	                        }
	                }
	                stackpointer = radius;
	
	                for (x = 0; x < w; x++) {
	
	                        r[yi] = dv[rsum];
	                        g[yi] = dv[gsum];
	                        b[yi] = dv[bsum];
	
	                        rsum -= routsum;
	                        gsum -= goutsum;
	                        bsum -= boutsum;
	
	                        stackstart = stackpointer - radius + div;
	                        sir = stack[stackstart % div];
	
	                        routsum -= sir[0];
	                        goutsum -= sir[1];
	                        boutsum -= sir[2];
	
	                        if (y == 0) {
	                                vmin[x] = Math.min(x + radius + 1, wm);
	                        }
	                        p = pix[yw + vmin[x]];
	
	                        sir[0] = (p & 0xff0000) >> 16;
	                        sir[1] = (p & 0x00ff00) >> 8;
	                        sir[2] = (p & 0x0000ff);
	
	                        rinsum += sir[0];
	                        ginsum += sir[1];
	                        binsum += sir[2];
	
	                        rsum += rinsum;
	                        gsum += ginsum;
	                        bsum += binsum;
	
	                        stackpointer = (stackpointer + 1) % div;
	                        sir = stack[(stackpointer) % div];
	
	                        routsum += sir[0];
	                        goutsum += sir[1];
	                        boutsum += sir[2];
	
	                        rinsum -= sir[0];
	                        ginsum -= sir[1];
	                        binsum -= sir[2];
	
	                        yi++;
	                }
	                yw += w;
	        }
	        for (x = 0; x < w; x++) {
	                rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
	                yp = -radius * w;
	                for (i = -radius; i <= radius; i++) {
	                        yi = Math.max(0, yp) + x;
	
	                        sir = stack[i + radius];
	
	                        sir[0] = r[yi];
	                        sir[1] = g[yi];
	                        sir[2] = b[yi];
	
	                        rbs = r1 - Math.abs(i);
	
	                        rsum += r[yi] * rbs;
	                        gsum += g[yi] * rbs;
	                        bsum += b[yi] * rbs;
	
	                        if (i > 0) {
	                                rinsum += sir[0];
	                                ginsum += sir[1];
	                                binsum += sir[2];
	                        } else {
	                                routsum += sir[0];
	                                goutsum += sir[1];
	                                boutsum += sir[2];
	                        }
	
	                        if (i < hm) {
	                                yp += w;
	                        }
	                }
	                yi = x;
	                stackpointer = radius;
	                for (y = 0; y < h; y++) {
	                        // Preserve alpha channel: ( 0xff000000 & pix[yi] )
	                        pix[yi] = (0xff000000 & pix[yi]) | (dv[rsum] << 16) | (dv[gsum] << 8) | dv[bsum];
	
	                        rsum -= routsum;
	                        gsum -= goutsum;
	                        bsum -= boutsum;
	
	                        stackstart = stackpointer - radius + div;
	                        sir = stack[stackstart % div];
	
	                        routsum -= sir[0];
	                        goutsum -= sir[1];
	                        boutsum -= sir[2];
	
	                        if (x == 0) {
	                                vmin[y] = Math.min(y + r1, hm) * w;
	                        }
	                        p = x + vmin[y];
	
	                        sir[0] = r[p];
	                        sir[1] = g[p];
	                        sir[2] = b[p];
	
	                        rinsum += sir[0];
	                        ginsum += sir[1];
	                        binsum += sir[2];
	
	                        rsum += rinsum;
	                        gsum += ginsum;
	                        bsum += binsum;
	
	                        stackpointer = (stackpointer + 1) % div;
	                        sir = stack[stackpointer];
	
	                        routsum += sir[0];
	                        goutsum += sir[1];
	                        boutsum += sir[2];
	
	                        rinsum -= sir[0];
	                        ginsum -= sir[1];
	                        binsum -= sir[2];
	
	                        yi += w;
	                }
	        }
	
	        Log.e("pix", w + " " + h + " " + pix.length);
	        bitmap.setPixels(pix, 0, w, 0, 0, w, h);
	        return (bitmap);
        
    	} catch (Exception e) {
    		e.printStackTrace();
    		return null;
    	}
            
    }

}
